Systems are known to protect people in the case of public emergency. For example, a toxic gas leak or risk of explosion may necessitate the need for evacuation of entire blocks of houses in a city or even the entire cite.
Such systems are typically based upon the use of one or more civil defense sirens that may be activated in the event of emergency. Upon the activation of such systems, people often turn on their radios or televisions to learn of the extent of the emergency, or they contact a local police department for instructions on how to reach a place of safety. Upon receiving instructions, residents may walk or drive to the place of safety.
Recent improvements in this area include the use of the telephone system. Using these resources, a local authority (e.g., police department, civil defense, etc.) may activate an electronic dialing system that places calls to individuals within the threatened area notifying them of the emergency.
Alternatively, at least some municipalities maintain a website of publically available information. Upon receiving a notice of a public threat, people may go to the website to obtain information about the threat and evacuation destinations.
While such systems are effective, instructions provided by such systems can be inadequate or misunderstood. In the event of a rapidly developing situation, a local police department may not be aware of the full extent of the danger. Alternatively, the area of the threat may grow, or the site may change based upon environmental conditions. For example, a fire may break out in a neighborhood and spread rapidly because of strong winds. Alternatively, an evacuation plan may be implemented for a hurricane or typhoon on one day, and on the next day or hour, the path of the storm may change. Accordingly, a need exists for better methods of promulgating evacuation information.